When flame roasting peppers or similar food products, it is necessary, or at least greatly preferred, that all of the surrounding surfaces of the product be directly exposed to the burner flame. The flame chars the outer skin of the product, which is then removed using a washing process. In industrial processes used for flame roasting peppers and other products, the product is typically exposed to a direct flame while being tumbled in a rotating drum or while being carried on a conveyor belt.
When carried on a conveyor belt, the product remains in a static (stationary) position on the belt unless acted upon, for example, by some mechanical or gravitational means which causes the product to rotate or otherwise move to a different position. The rotation or movement of the product on the belt is desirable to ensure that all surfaces of the product are exposed to the flame. In addition, it is desirable that the rotation or movement of the product be controlled and timed in a way so as to ensure that all surfaces of the product receive adequate direct exposure to the flame but no portion of the product is overexposed. Such overexposure decreases both the yield and the quality of the roasted product.
Consequently, a continuing need exists for improved, economical, efficient, low maintenance systems which are highly effective for rotating or otherwise changing the positional orientation of peppers or other individual food product items or pieces while conveying the products through flame roasting systems and other processing systems so that the entire outer surface of the product is subjected to uniform treatment. Additionally, however, such systems for rotating or otherwise moving peppers or other products on a product conveyor belt should also operate in a manner which ensures that the products are gently handled and are not subjected to excessive impact forces. Subjecting peppers and other products to excessive impact forces can physically break, mark, or otherwise degrade the products. Damaging impact forces can be caused, for example, by (a) impacting the products with physical mechanisms used for moving the products, (b) causing the products to collide with physical structures positioned for product displacement, (c) causing the products to collide with each other, or (d) dropping the products from one elevation to another.
U.S. Pat. No. 6,132,748 discloses an apparatus for UV light disinfection of fruits and vegetables wherein the conveyor which carries the products through the apparatus can be formed of a continuous series of lateral rollers which are caused to rotate as they carry the product through the apparatus so that all exterior surfaces of the product are exposed to the disinfecting illumination of the UV light. Unfortunately, however, roller conveyor systems of the type used in the disinfecting apparatus of U.S. Pat. No. 6,132,748 have significant shortcomings and disadvantages. In addition to their high, cost, these systems can damage the product in ways which adversely affect the product yield, integrity, shape, and color.
U.S. Pat. No. 6,099,882 discloses an apparatus for roasting skinned products such as peppers, onions, garlic, and potatoes wherein the conveyor system which carries the products through the apparatus comprises (a) a conveyor formed of a continuous series of lateral rollers having sprockets attached to the ends thereof, (b) a drive chain which continuously drives the conveyor through the apparatus in a clockwise direction, and (c) a spinner chain which is driven in a counterclockwise direction to engage the sprockets of the rollers and thereby cause the rollers to rotate as they carry the product through the apparatus.
Unfortunately, conveyor systems of the type used in the roasting apparatus of U.S. Pat. No. 6,099,882 also have significant shortcomings and disadvantages. In addition to having the same general deficiencies as the system described in U.S. Pat. No. 6,132,748, conveyor systems of the type described in U.S. Pat. No. 6,099,882 have a limited range of control and the mechanical movement of these systems in a heated environment is prone to failure.
U.S. Pat. No. 6,060,104 discloses a grilling apparatus for hamburgers and chicken breasts in which the patties or chicken breasts are turned over (flipped) one time as they pass through the apparatus by dropping the patties or chicken breasts from a first conveyor at a higher elevation to a second conveyor at a lower elevation. Unfortunately, conveyor systems of the type used in the grilling apparatus of U.S. Pat. No. 6,060,104 also have significant shortcomings and disadvantages. For example, the individual product items or pieces must be of substantially the same weight and shape in order to flip properly. In many instances, the product sticks to the belt and does not flip at all. In addition, these systems have a limited range of control and the flip or fall which changes the orientation of the product can cause even greater product damage and loss of yield.
Another type of system used in the art for rotating or otherwise changing the positional orientation of peppers or other food products on a conveyor as the products are carried through a roasting apparatus or other treatment system consists of a thumper that mechanically lifts and drops the conveyor belt in a manner which causes the product to bounce. Unfortunately, these systems cause significant machine and belt wear and are often too aggressive, often resulting in substantial product breakage.